Electric motors are used in many applications for the movement of various mechanical devices. There are many different kinds of electric motors. For example, alternating current synchronous and reduction motors, direct current shunt, series or compound motors.
One type of electric linear motor that is used in precision applications is the brushless motor with permanent magnet stators, polyphase moving coil armatures, sinusoidal commutation, and hall effect commutation sensors. These types of electric linear motors do not have commutation brushes or any other physical contact between the stationary and moving components. Therefore, these motors are preferably used in clean room environments and in the manufacture of semiconductors where a clean environment and precision motion control is required.
While these types of electric motors accomplish the purposes for which they have been intended, there is an ever increasing need to improve the operation and precision control of such electric motors so as to enhance their operation and application to the precision motion control requirements of different manufacturing applications, such as semiconductor manufacturing.